Marcia Wallace, who played Bart's fourth-grade teacher Edna Krabappel on Fox's animated comedy "The Simpsons" and Bob Newhart's wisecracking receptionist Carol Kester on the classic 1972-78 CBS sitcom "The Bob Newhart Show," has died at the age of 70.

Wallace died at home in Los Angeles Friday night, surrounded by friends and family.

Contrary to earlier reports that she died of complications from breast cancer, her son, Michael Hawley, told the Times Saturday afternoon that she had been in failing health for the last several months and died due to complications of pneumonia. Wallace, who had been diagnosed with breast cancer in 1985, was an advocate for breast cancer awareness.

"Simpsons" executive producer Al Jean said Saturday that the character of Mrs. Krabappel -- who married Ned Flanders in later seasons -- will be retired from the show.

"You fall in love with these people when you see them as characters on television, but when met Marcia you loved her even more," Jean said. "She was sweet, funny, not at all pretentious. She was a breast cancer survivor for over 20 years and she was always chipper and just a wonderful person to be around."

Jean said the next new episode of the long-running animated series, airing Nov. 3, will include a tribute to Wallace.

Before her death Wallace "recorded several lines which will appear in upcoming shows," Jean said. "But I don't intend to have anyone else play Mrs. Krabappel. I think Bart will get a new teacher and Ned Flanders will be a widower again."

In 1992, Wallace won an Emmy for her vocal performance as Edna Krabappel.

For baby boomers, though, she will always be the quick-witted receptionist for button-down psychologist Bob Hartley (Newhart) on the beloved “The Bob Newhart Show.”

“We were part of the culture of the '70s,” said Wallace an a 1991 interview with The Times about her experience on the series. “I thought we had something really magical.

Wallace, who guest starred in such series as "Full House," "Taxi" and "Murphy Brown," was married to hotelier Dannis Hawley, who died in 1992. Their son Michael appears with Wallace in "Muffin Top."

Update, 3:10 p.m.: An earlier version of this post quoted a Deadline interview with Wallace's friend writer/director Cathryn Michon, who stated that Wallace had died of complications of breast cancer. In addition, Wallace was mistakenly identifed as the voice of Ned Flanders' first wife, Maude.